Adjustable diameter sheave



Sept. 16, 1952 w. A. WILLIAMS 2,610,515

ADJUSTABLE DIAMETER SHEAVE Filed Feb. 24, 1949 7 Sheets-Sheet 1 I Q WITNESSE Y INVENTOR:

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Sept. 16, 1952 w. A. WILLIAMS ADJUSTABLE DIAMETER SHEAVE Filed Feb. 24, 1949 7 Sheets-Sheet 2 INVENTOR:

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WITNESSES Sept. 16, 1952 w. A. WILLIAMS 2,610,515

- ADJUSTABLE DIAMETER SHEAVE Filed Feb. 24, 1949 7 Sheets-Sheet s W I TNESSES I N VEN TOR:

% ATTORNEYS.

S ept. I6, 1952 w. A. WILLIAMS v 2,610,515

' ADJUSTABLE DIAMETER SHEAVE 1 Filed Feb. 24, 1949 "r Shee ts-Sheet 4 BY I 6W A TTORNEYS.

Sept. 16, 1952 w. A. WILLIAMS 2,610,515

ADJUSTABLE DIAMETER SHEAVE Filed Feb. 24, 1949 7 Sheets-Sheet 5 I'll WITNESSES I N V EN TOR:

9% 20 illiam fl WZZZ1'am-, o 6% BY MW A TTORNEYS.

Sept. 16, 1952 w. A. WILLIAMS 2,610,515

ADJUSTABLE DIAMETER SHEA-VE Filed Feb. 24, 1949 7 Sheets-Sheet s k 91 L2 93 W1 TNESSES m I N V EN TOR:

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Sept. 16, 1952 w. A. WILLIAMS ADJUSTABLE DIAMETER SHEA-VE 7 Sheets-Sheet 7 Filed Feb. 24, 1949 WITNESSES 'INVI '}N7 'OR.- Q 2 L/ Wdizam xii/171111412125 BY G n/411 zw ATTORNEYS.

that shown in Fig. 1;

Patented Sept. 16, 1952 UNITED STATES PATENT OFFICE 7 2,610,515) 1M o ADJUSTABLEDIAMETERSHEAVE William A. Williams, Philadelphia, Pa., assignor to The American Pulley Company, Philadelphia, Pa., a corporation of Pennsylvania Application February 24,1949, Serial No. 78,116

18 Claims; (Cl. 74 -230.17) V This invention relates" generally to adjustable diameter sheaves and more particularly to a form thereof which is so constructed that any tendency of such sheaves to become non-adjustable because of rust. or corrosion is substantially. eliminated. J j

In the verybeginning of the development of the multiple groove adjustable sheave. the'art encounteredthe difiiculty of the freezing of the movable parts due to'rust or corrosion or the like. The resultof such freezing was'the loss of the important feature of adjustability and, in efiect,

the conversion of the sheave from an adjustable one into a fixed. and non-adjustable one. This.

problem has been acontinuing onein the art in spite of numerousefiorts to solve it by'a variety of means. The present invention, as its principal object, is directed toward'the solution of this problem and provides a multiple groove adjustable diameter sheave which is not subject to the defect of freezingof the movable parts by which the adjustment feature is obtained. This invention'combines easy and permanent adjustability with positive locking and flxing'of the sheave for running condition, The invention involves the 1 is particularly important where the sheave must be within the hub sizes available and; yet have a very large bore.

Still further-objects and advantages of thisinvention will become-apparent from the following detailed description of "a preferred embodiment thereof with suggestedmodified forms, as illlu'strated in the accompanying drawings.

Fig.1 of these drawings is an end elevation of a multiple groove adjustable sheave illustrating apreferredform-of theinvention:

Fig. 2 is a longitudinal sectional view. or the same taken as indicated by the lines and arrows 11-41 inFigilj Fig. 3"is' an end elevation taken oppositely to Fig. 4 -is a transverse sectionalview of the same taken as indicated-bythe linesand arrows IV-IV i "in Fig.2;

Fig. 5 isa longitudinal sectional viewsimilar to Fig. Zshowing"various parts in their moved position;

Fig. 6 is an exploded perspective View. or a tapered ring;

2 Fig. 7 lsa perspective View of a flange showing the nesting lug flanges;

Fig. 8 is a perspective view of another type of flange included in the assembled flange unit; v

Fig. 9 is a perspective'view of still another type offlange included in the assembled flange unit;

Fig. 10 is an end elevation similar to Fig.1, of a modified form of pulley sheave; I

Fig. 11 is a longitudinal sectional view of the same similar to Fig. 2 taken as indicated by the lines and arrows XI -XI in Fig. 10;

Fig. .12 is a transverse sectional view of the same, similar to Fig; 4; taken as indicated by the lines and arrows XIL-XII in Fig. 11; 7 o

Fig. 13 is a longitudinal sectional view of the same. similar to Fig. 5 taken as indicated-by the lines and arrows XIII-XIII in Figs. 10 and 12 and shown in their moved position;

Fig. 14 is another end elevation of a second modified form of pulley sheave;

Fig. .15 is aflongitudinal sectional view of the same taken asindicated' by the'lines and arrows XV- -XV in Fig, 14;

Fig. 16 is a transverse sectional view of the :same taken as indicated by the lines and arrows Ito be understood that it is not intended thereby to limit the invention to, this detaileddescriptio-n of an illustrative embodiment thereof. Each term adopted is intended to include all equivalents thereof which operate in a substantially similar manner to accomplish asubstantially similar result. o 7

The invention shown in the drawings may be "analyzed conveniently into the following prin- 45 cipalelements in order to facilitate a detailed desoription thereof: a split exteriorly tapered bushing, lliga split interiorly tapered hub II, complementary multiple flange units I2 and I3 mounted on saidhub l.;|, a tapered wedge element in the form of a'ring'. Hi carrying draw bolts [5, and a flange adjustment ring. [6 in threaded engagement withfboth of said multipl flange units I2 and I3, said bolts being constrained againstaxial movement in said wedge element. I The split exteriorly tapered bushing It is formed with an interior key-way I! for keyed engaged with a shaft, not shown, and with a longitudinally extending split 2I. The split 2I permits the bushing II] to be compressed into a gripping engagement with a shaft when the sheave is mounted thereon which avoids looseness and resulting vibration. The bushing is likewise rendered capable of expansion to facilitate the removal of the pulley from the shaft on which it is mounted. This bushing I is slidably mounted within the hub II which is interiorly tapered to correspond with the exterior tapering of the bushing I0. A longitudinally extending split 22 is provided in the hub II to permit expansion by the operative eflects of the bushing II.- that in the assembly of the pulley, the bushing I0 is under compression and the hub 'II is under expansion. In this way the shaft is positively gripped by the compressed bushing I0 and the flange units I2 and I3 positively grip the expanded hub II. V

In order to force the hub II and bushing III in operative longitudinal movement relative to each other, a tapered ring I4 is. provided". This ring 14 is composed of three elements 23', '24and 25 assembled into a unit by means of screws 26. See exploded perspective view in Fig. 6. The element 23 .is formed with .a flange 21 .to cooperate with a. corresponding circumferential ledge or shoulder formed in the hub .II when pressure is being exerted to move the bushing- III outwardly by means of. the draw bolts I5. The element 24 is exteriorly tapered to cooperate with similar interior tapering within an end .of the hub II. .It will be noticed that this tapering between the element 24 and the end of the hub I I is relatively steeper and sharper than that between the bushing III and hub II. By providing the steep taper between the .element 24 and. the end of the hub II, the operative disengagement between these elements becomes automatic as the draw bolts I5 are loosened. The steep taper eliminates the possibility of freezing between the elements. The element '25 which is mounted on the outer end of the elemen'tldis provided with two countersunk openings3l to receive and partially enclose the Allen heads 32 of the draw bolts I5. Thus the heads 32 of the draw bolts I5 will abut against the element 25 when pressure is being applied to disengage the bushing I0 and the hub II; and similarly, the heads 32 of the draw bolts I5 will abut against the outer face of the element 24 when pressure being applied to engage the bushing I0 and "the hub 'I I. The

larly inclined flanges 33, .34, and '35, and the other unit I3 is made up of a plurality of similarly inclined flanges 36, 31 and 3 8. The flanges of unit I2 are oppositely inclined to the flanges of the unit I 3. It will be clear from Figs. '2 and 5 of the drawings'that the flange units I2 and I3 cooperate to form a plurality of adjustable sheaves, Fig. 2 showing the sheaves in the extreme closed position and Fig. 5 in the extreme open position. The component flanges of the flange units I2 and I3 are held together in units It will be clear from the above description by means of the Allen headed bolts 40 and 4|. The flange units I2 and I3 are keyed to the hub I I by means of the conventional keys 42.

The flange 33 (see Fig. 7) is formed with axially extending lugs 43 which are equally spaced circumferentially to provide openings therebetween to receive lugs 44 formed on the flange 36 (see Fig. 8). The lugs 44 are threaded .to engage the adjustment ring I6 which. is also in threaded engagement with the flange 33 as shown in Fig. 2. The threads on the inside and outside of the ad- J'ustment ring I6 are opposite so that the rotation of thering It will cause the flange units II and I2 to move in. opposite directions as the ring I6 is .rotated. The lugs 43 which extend through the flange-36 abut against the face of flange 34 (see Fig. 9). The flange 34 has similarly spaced lugs 45 which project through the adjacent flange 3'I andabut against the face of the flange 35 which is formed with lugs 46 projecting through the adjacent flange 38. Each of the bolts M, which bind the flange unit I2 into a unit,.is in threaded engagement at one end with one of. the lugs 43 on the flange 33 with its Allen head recessed into one of the. lugs'46 on the flange 35. The flange unit I3 is similarly formed from the flanges 36, 31 and 38 which are bound together by th bolts 45, the lugs 4'! and48 extending through adjacent flang'es34 and 35.

In operation, the above described sheave is mounted on and keyed to a shaft by means of the key way I] formed in the bushing I0. llhe flanges are adjusted .to the desired position by turning the adjustment ring I6 by means of a spanner wrench inserted holes 50 formed in the adjustment ring Iii-for that purpose. The .Allenheaded draw bolts I 5. are then tightened which causes the tapered ring I4 .and the bushing- III to be drawn. toward each other, resulting in the contraction of the bushing III and the expansion of the hub II thereby fixing the flange units I2 and I3 tightly in place and at the same time causing the bushing II] to grip the shaft tightly. It will been seen by reference to Fig. .2 that the tapered ring I4 exerts a concentrated expansion at the left end of the hub II, and. that the distributed effect of this force is a tightening of the threaded engagement between the adjustment ring I6 and the flanges 33 and .36. This has alocking chest to prevent rotation of the flange adjustment ring I6 when the sheave is in operation. .As pointed out above, the taper of the tapered ring I4 is steep when compared with the taper of the bushing III. This steep taper of the ring I4 insures easy withdrawal of the ring I4 from wedged engagement with the hub II. It will be appreciated from the above description that all looseness in the assembled and operative sheave is eliminated with the destructive vibration caused by such looseness. When it becomes necessary to adjust the flange units I2 and I3 byrota-ting the ring I6, it is a very simple matter to loosen the assembly by turning the Allen headed draw bolts I5 so that the ring I4 and the bushing III are moved away from each other. .In this loosening operation, the circumferential ledge 30 formed on the hub abuts against the flange 21 formed on-thering I4, and the ring I4 thereby anchored to support the draw bolts I5 for axial thrust transmitted to the bushing III. In this way the hub II and the bushing II) are moved axially and in opposite directions relative to each other. The

loosening effect of this relative motion will be obvious.

In Figs. to 13 inclusive, a modified form of the invention is illustrated. It will beseen from the inspection of these figures of the drawings that the operative principle thereof is the same as that of the preferred form described above.

Since the flange units 55 and 56 are similar to the above described flange units Hand I3respectively, a detailed descripiton would be super- The unit 55 is made up ofsimilarly inclined flanges 5'l, 59, t land 63, held together bythe bolts 66 as shown in Fig. 13. The unit 56 is made upof similarly inclined flanges 58', 5B, 62 and 64 held together by the bolts 65 as shown in Fig. 11. The flanges 51 and 58 are in threaded engagement with adjustment ring 61 which is generally similar to the previously described ring it in the preferred form. A tapered ring 68 in this modified form functions similarly to the tapered ring H5, but the former is all in one piece in contrast to the three component elements of ring it. Further, the ring 68 does not, have a flange like the flange 21 which interlocks the ring it with the hub II. The function of the flange 27 in the preferred form is performed by a conventional collar or snap ring 13 on thedraw bolts 12 as will be explained in more detail later.

Hub l9 and bushing ll are analogous to hub II and bushing Iii respectively in the preferred form and are similarly tapered and split at 15 and 16. The bushing H is keyed to a shaft bymeans of key way 17. Allen headed draw bolts 12 function similarly to the draw bolts I5 except that the draw bolts 12 carry snap rings T3 which abut against the end of the hub. iii when exerting thrust on the bushing i I. The draw bolts l2 are recessed in longitudinal channels formed in the hub l0 which permits arelatively large bore with out unduly enlarging the hub size. The operation of this modified form will be obvious from the above description in view of 'thejremarks relating to the operation of the preferred form.

A second modification of the invention is shown in Figs. 14 to 17 inclusivewhich is the same as the modification just described above except for bushing 80, hub 83 and Allen headed draw bolts 82. A greater number of flanges is shownin this second modification since it lends; itself easily to a large number of sheaves with the bushing 80 completely within the hub 83. Elements in this second modification which are the same as corresponding elements in the first modification are therefore given the same identifying numerals in both modifications. The bushing 85 is formed with longitudinal slots 8! which give flexibility for compression and expansion and also receive the draw bolts 82 which threadedly engage the bushing 86. See Figs. 15 and 18. The bushing 86 and hub 83 are tapered as in the two forms described above and for the same purpose. Collars 84 are integrally mounted in a conventional fashion on the draw bolts 32 by means of pins 85. 'The collars 84 are recessed into the hub 83 as shown in Fig. 15 and provide an anchorage for the draw bolts 82 when exerting an axial thrust to the bushing 8d. The function of this collar 64 is analogous to that of the collar or snap ring 13 shown in Fig. 11 and described in connection therewith. Flange unit 90 made up of flanges 82 and 93, and flange unit 5| made up of flanges 95, M and 36 are so similar to the other flange units described above that no detailed description will be necessary. The operation of this second modification is the same in principle as the other forms described above and will be clear from the above description.

While this invention has been described above in considerable detail and certain modifications thereof suggested, it will be apparent to those skilled in the art that various other changes and in abutting relation to an end of said split hub,

a draw bolt operatively connecting said ring and said bushing and a pair of complementary flanges mounted on said hub with capacity for axial movement relative to said hub and to each other.

2. The invention of claim 1 characterized further by the fact that said ring is tapered to correspond with a complementary interior tapering within the end of said split hub.

3. In an adjustable diameter sheave, an interiorly tapered split hub, an exteriorly tapered bushing slidably mounted within said interiorly tapered split hub, a tapered ring mounted in one end of said hub, an abutment means for preventing said tapered ring from being disengaged from said hub, a draw bolt rotatably mounted in said ring and restrained against axial movement relative'to said ring, said draw bolt being in threaded engagement with said tapered bushing, and a pair (of complementary flanges mounted on said hub with capacity, for axial movement relative to said hub and toy each other.

, 4. The invention of claim 3 characterized further by an adjustment ring in threaded engage= ment with said flanges whereby the rotation of said adjustment ringwiil cause said flanges to move in opposite axial directions.

5. The invention of claim 3 characterized further by the fact that said tapered bushing is longitudinally split.

. 5. The invention of claim 4. characterized further by the fact that said flanges are keyed to said hub.

7. In an adjustable diameter sheave, an exteriorly tapered split bushing, an interiorly tapered split hub mounted on said bushing, a tapered ring mounted in interlocking relation with said hub opposite the inner end of said bushing, a draw bolt mounted in said ring and having its outer end threadedly engaged with the inner end of said bushing, a pair of complementary flange units mounted on and keyed to said-hub with 7 capacity for controlled limited axial movement.

and an adjustment ring in threaded engagement with each of said flange units and having capacity for rotary but not axial motion.

8. The invention of claim 3 characterized further by the fact that the taper of said tapered ring is relatively steep in comparison with the more gradual taper of said bushing.

9. The inventionof claim 3 characterized further by the fact that said draw bolt is in threaded 7 onsaid hub with capacity ifor axial movement relative to said hub and to :each other.

.11.. The invention of :claim 11.0 characterized further by the .fact that said collar is recessed .into the .hub intermediate the ends thereof, and said draw bolt is recessed into a longitudinal groove.

12. The invention .of claim 11 characterized further by the -fact that said bushing is completely housed within :said hub.

13.. .The invention of claim 12 characterized further by the fact thatsaid hnshingis cut away longitudinally over a portion of its length to receive :the said draw bolt.

14. An adjustable diameter sheave comprising an .exteriorly tapered bushing adapted to be mounted on a shaft, :an interiorly tapered split hub,.said 1111b being tapered oppositely and complementally :to the tapering of said bushing and slidably positioned thereon; ,arotatable threaded a-dju-stment means .mounted .at one end iOf said hub and operatively connected to said bushing for positively;forcing said bushing .in axial movement relative to saidhub Without effecting the positioningof said bushingon a shaft, .said adjustment means being exposed for operation, and a pair of flanges mounted on saidhub, screw means rotatable :about'the aforesaid end of the hub for adjusting the flanges relative to .each other to change the effective diameter of .thesheave, and releasable means by which'the flange adjusting means is fastened to the hub for security against displacement in adjusted positions.

15. The invention of claim 14 characterized further by the fact that a plurality of said rotatable threaded adjustment means is provided and positioned :circumferentially at the end of said huh.

It. An adjustable diameter sheave comprising an exteriorly-tapered bushing, an internally tapered split hub, a pair of flanges mounted on said hub, means for adjusting the flanges relative .to each other to change the eiiective diameter of the sheave, means at one end of said hub operatively connected to said bushing for positivelyiorcingsaid bushing axially relative tosaid .hub 'to effect contraction .of said bushing and expansion of said .hub, and releasable means .connected to the hub for securing the flange adjusting means against accidental displacement in adjusted positions.

17.. In a sheave, a split hub sleeve with its bore tapered inwardly from opposite ends; at least one pair of opposing sheave .flanges mounted -.on the sleeve with Acapacity for being .adjusted laterally relative to each other along the sleeve; tapered opposing wedge elements engaging into opposite ends of the hub bore; and :means for drawing one wedge element toward the other to expand the 'hub sleeve "within thesheave flanges.

18. In assheave, asplitlhub sleeve with a bore having a long inward taper :at "one end, and a short and more abrupt taper at the opposite end terminating .in an annular internal shoulder; at least one pair oi-opposing sheave flanges mounted on the sleeve with .capacityfor adjustmentlaterally relative to each other along the sleeve; a tapered wedge hns-hingfltting into the long taper bore end of the .hub sleeve; a'wedge element fitting into theishort taper .:b.or.e end of the sleeve and :having a .flangeinspaced .confronting relation .to the annular shoulder within sleeve bore; and adjusting screws .zconstna'ined :to rotation .in the wedge element with their shanks threadedly engaging into .the...inner end of the bushing, whereby, upon turning the screws one direction, the wedge element and the bushing are drawn toward :each other to expand the sleeve within the isheaveflanges, and whereby,

when the vs-crewszare :turnedin-the opposite .direction, the wedge elementis flrstretracted relative to the hub sleeve and said sleeve subsequently dislodged fromthe bushing through cooperation ibetweenthe flange :oi "the wedge element and the internal shoulder of the sleeve, .to :permit cirnnmferential contract-ion of the latter for release of the sheavefianges.

WILLIAM A. WILLIAMS.

REFERENQES CITED Elie following references are of record in the :file .of -thispatent:

' UNITED STATES PATENTS Number Name .Date

308,639 Stevens Dec. 2, .1884 339,480 7 .Massett .Sept. 11,1888 1,439,424 Knudsen Dec. 19, 1922 1,981,196 Riblet Nov. 20, 1934 2,172,230 Watson Sept. 5, 1939 2,289,965 Herman July .14, 1942 2,480,222 Carlson Aug. 30, 19,49

FOREIGN PATENTS Number Country Date 512,568 Great Britain Sept..20, 1939 

